Patent GB-775625-A (GB)
Title: Improvements in or relating to extensible linkages, such as utilized in expansible bracelets
Inventor: AUGENSTEIN KARL CHRISTOF
IPC: A44C5/08
Filed: 1955-07-11
Abstract: 775,625. Bracelets. SPEIDEL CORPORATION. July 11, 1955, No. 19979/55. Class 43. A self-retracting expansible bracelet or linkage comprises a series of top links, the ends of which are adjacent to each other when the linkage is retracted, articulated to one another by connecting- means comprising bottom links respectively pivotally connected at one end to adjacent top links and at the other end pivoted to bottom link connecting-members extending generally longitudinally of the linkage, the said pivotal connections having axes that are generally perpendicular to the faces of the bottom links, spring means being associated with the links to urge the top links towards each other while permitting longitudinal extension of the linkage. Figs. 3 and 4 show the underside of a bracelet in the retracted and extended positions respectively, the normally top links L being in the form of hollow square plates 14 covered by ornamental top shells 15, Fig. 6, secured thereto by inturned lugs 101, and the bottom links B each formed by a plate 20 with a hollow cap or shell 21 secured to it, e.g. by inturned lugs. Pivotal connection between a top link L and a bottom link B is provided by means comprising a hollow spacing block 17, Figs. 4 and 8, which is located transversely to the longitudinal direction of the bracelet and has its bottom portion pivotally connected to the plates 20 of two bottom links B by hollow tubular rivets 23, after which lugs on two sides of the spacing block are bent around the adjacent sides of the plates 14 of the top links. In the example the bottom link connecting-members C each consist of two similar strip-metal pieces 11a, 11b, Fig. 6, hingedly connected together end to end by a tongue 12b on the former engaging within a slot 13a in the latter. The outer ends of the strips 11a, 11b each have an offset lug which extends into a hole in the plate portion 20 of a bottom link B, Fig. 6, to provide the pivotal connection, the ends of the lugs being peened to form a head 27. Before the hollow caps 15 and 21 are attached to their respective plates 14 and 20, helical tension springs 30 with extending end fingers 31, 32 are inserted through the eyelets 23 which form the pivots between the top links L and bottom links B, and the fingers 31 are held upon the upper faces of the plates 14 by lugs extruded upwardly from the latter. The fingers 32 extend along the underside of the plates 20 and are held in place by engaging a side wall of the cap 21 that is finally secured over each plate 20. Detachable spacing-pieces or links 200, Fig. 13, may be inserted between two adjacent top links L when they are extended apart, the top surface of a spacing-link being similar to that of a link L, whilst its two opposite longitudinal edges are provided with inwardly bent prongs 202 which form opposed U-shaped pockets arranged to receive the respective pairs of bottom link connecting-members 11a, 11b. In a modification, Fig. 23 (not shown) two bottom links are pivotally mounted on a single eyelet at each transverse side of the top links L, and in further modifications the bottom link connecting-members comprise single thin strips of flexible material, e.g. spring steel, with their opposite ends pivotally connected to the bottom links B, or coil springs arranged with their axis perpendicular to the longitudinal centre line of the bracelets and their ends extended laterally and bent to make pivotal connection with the bottom links.